Liu Baogen, Li Haoyang, Ma Xianchen, Chen Ruofei, Wang Shaobin, Li Liqing
School of Energy Science and Engineering, Central South University Changsha 410083 China
School of Material Science and Engineering, Central South University Changsha 410083 China.
RSC Adv. 2018 Nov 20;8(68):38965-38973. doi: 10.1039/c8ra05523h. eCollection 2018 Nov 16.
A high surface area activated carbon prepared by an innovative approach using glucose as a carbon source and neutral potassium citrate (PC) as an activator was compared with the porous carbon from glucose using corrosive potassium hydroxide (KOH) as an activator. The PC method showed two notable advantages over KOH activation. The PC method not only significantly increased the yield of the activated carbon, particularly at high carbonization temperatures without sacrificing porosity, but also enhanced the oxygen content in the activated carbon. After investigating CO adsorption on these activated carbons, a remarkable uptake of 3.57 mmol g at 25 °C at 1 bar was observed by the glucose-PC-derived carbon sample, which possessed the highest oxygen content. In addition, the glucose-PC-derived carbon samples exhibited higher CO/N selectivity than the glucose-KOH derived samples. Coupled with the density functional theory (DFT) analysis that focused on the binding energy calculation, the doped oxygen-containing functional groups, such as carboxyl and hydroxyl groups, could effectively enhance the adsorption of CO.
采用创新方法制备的高比表面积活性炭，以葡萄糖为碳源、中性柠檬酸钾（PC）为活化剂，并与以腐蚀性氢氧化钾（KOH）为活化剂由葡萄糖制备的多孔碳进行了比较。与KOH活化相比，PC法显示出两个显著优点。PC法不仅显著提高了活性炭的产率，特别是在高碳化温度下且不牺牲孔隙率，而且还提高了活性炭中的氧含量。在研究这些活性炭对CO的吸附后，由葡萄糖-PC衍生的碳样品在25℃、1巴下观察到显著的吸附量，为3.57 mmol/g，该样品具有最高的氧含量。此外，由葡萄糖-PC衍生的碳样品比由葡萄糖-KOH衍生的样品表现出更高的CO/N选择性。结合专注于结合能计算的密度泛函理论（DFT）分析，掺杂的含氧官能团，如羧基和羟基，可有效增强对CO的吸附。
